Head positioning signal generating apparatus

ABSTRACT

A helical scan type video tape recorder adapted to perform in any one of a plurality of special reproducing modes, includes first and second rotary magnetic heads for reproducing a video signal from parallel tracks on a magnetic tape; first and second electrically deflectable, bi-morph leaves for supporting the first and second rotary magnetic heads; a control signal generator supplying a bias potential to the bi-morph leaves in accordance with the speed of movement of the tape so that the heads accurately scan the tracks; a hysteresis erase signal generator supplying a bias potential to the bi-morph leaves after the respective heads have completed scanning each track for removing hysteresis distortion from the respective bi-morph leaves; and a predictive potential generator for supplying a bias potential to the bi-morph leaves after the hysteresis distortion has been removed so that the magnetic heads accurately scan the beginning of the tracks, including an UP-DOWN counter for producing an output as a function of the speed of movement of the magnetic tape, the position of the heads relative to the tracks, and the rotation of the heads, and first and second sample-hold circuits for sampling the output of the counter at the end of the scan of a respective track by the first and second magnetic heads, respectively, and supplying the respective sampled outputs to the first and second bi-morph leaves, respectively, when the first and second heads begin scanning the next respective tracks.



